ELECTRONIC SIGNATURE DEVICE, ELECTRONIC SIGNATURE VERIFICATION DEVICE, ELECTRONIC SIGNATURE METHOD, PROGRAM, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To detect what piece of important information in an electronic document is altered, or whether or not data of the important information are simply changed to unimportant information by data processing mistakes, when alteration of the electronic document is detected.;SOLUTION: An important information acquisition part 103 acquires the important information (such as a date, an amount, an issuing destination) in the electronic document. An electronic signature generation part 104 generates electronic signature data (such as a signature value and attribute information of an area) for each piece of important information, and further generates electronic signature data for the whole electronic document. All the pieces of generated electronic signature data are associated with image data and stored in a data storage part 106.;COPYRIGHT: (C)2009,JPO&INPIT